Protein-Sparing Modified Fast (PSMF) Diet Program in San Antonio, TX

What is a Protein-Sparing Modified Fast?

The goal of a protein-sparing modified fast (PSMF) is to reduce calories to the lowest possible threshold while still eating enough protein to preserve lean muscle mass and micronutrients to avoid any type of deficiency. This program includes dietary components in addition to medical and behavioral aspects. To be successful, serious commitment is required to change undesirable eating habits, which will help patients reach and maintain their desired weight long-term.

PSMF is typically used for individuals who are at least 100 pounds overweight, have a body mass index (BMI) of 40 or higher, or have a BMI of 35 with more than one chronic disease or condition. This program is designed to help an obese individual reach a healthy body weight, as determined by his or her healthcare provider or registered dietitian. Healthcare providers are used as part of this program because they are able to clinically:

Monitor/evaluate overall health

Answer questions

Monitor blood work

Review food and supplement intake

Teach behavior modification techniques

How Does PSMF Work?

The protein-sparing modified fast involves eating very limited amounts of fat and carbohydrates while consuming a reasonable amount of protein. As part of this program, a typical dieter may consume 100 grams or more of protein per day, depending on his or her lean body mass. The goal behind PSMF is to create as large of a daily calorie deficit as possible while also preventing lean muscle breakdown. This is why consuming at least the minimum amount of daily protein is critical to success on this diet.

While participating in a PSMF program, participants consume only lean meat, seafood, poultry and a limited amount of low-carbohydrate vegetables. PSMF dieters work with a medical professional to help determine the optimum amount of protein necessary per day. Carbohydrates such as bread, crackers, fruit, sugar, soda and desserts—as well as additional forms of fat—are not allowed on this program. The high protein intake is designed to prevent the body from using its own protein stores for energy in muscles, tissues and cells.

Is PSMF Safe?

PSMF is an example of a very low-calorie diet (VLDC). Generally, a VLDC involves eating less than 800 calories per day. Normally, a diet with such a limited caloric intake would be nutritionally deficient, but the PSMF incorporates various vitamins, minerals and essential fatty acids to maintain body functions. This is what separates protein-sparing modified fast programs from crash diets or cleanses.

This program is safe, particularly when used for short periods of time—usually around one to two months. Participants generally avoid cardiovascular exercise while participating in PSMF because it can cause a dangerous calorie deficit. Weight training while on the diet is acceptable, but patients should check with their physicians before doing so. As with any diet, success only occurs when an individual is willing to consistently follow the program guidelines, work with his or her healthcare team, and make permanent lifestyle changes.